Means for controlling variable speed gears



pt- 28, 1937. A. c. WICKMAN 2,094,313

MEANS FOR CONTROLLING VARIABLE SPEED GEARS Filed Dec. 5, 1956 l l I m cm N ,Q' i N /7- C"- Max 7mg Patented Sept. 28, 1937 2 094 313511 UNITED srArEs A'rEN'r OFFICE MEANS FOR CONTROLLING VARIABLE SPEED GEARS Axel Charles Wickman, Coventry, England Application December 5, 1936, Serial No. 114,507

In Great Britain January 13, 1936 "3 Claims. (01. 74364) This invention has for its object to provideiminders r arranged in a block around the shaft a proved means for controlling variable speed and each containing one of the said plungers. gears. Pressure fluid admitted to any one of the cylinders The invention comprises the combination of 1" through a pipe 11., one of which is prow'ded for a slidable gear controlling member, a plunger each of these cylinders, causes the corresponding 5 carried in a fixed cylinder for moving the slidplunger to act on the adjacent side of the cylindriable member in one direction, this cylinder cal member g in opposition to the first mentioned (when the apparatus is in use) being constantly plunger e. supplied with pressure fluid, a plurality of abut- The admission or release of fluid to or from 1O ments for determining the positions to which any of the cylinders 1' is controlled by a valve or the said slidable member can be moved, and fluid valves (not shown) which may be moved from operated means for moving the said slidable memone position to another by hand or automatically. ber towards the abutments in opposition to the When fluid is admitted to any one of these cylaction of the said oonstantly-supplied pressure inders it moves the corresponding plunger (e. g.

fluid. the plunger n outwards, and by the action of 15 In the accompanying sheet of explanatory this plunger on the cylindrical member g the, drawing: slidable shaft or is moved in opposition to the said Figure 1 is a sectional elevation of a variableconstantly-supplied pressure fluid acting on the speed gear provided with the invention. plunger 8 until the pl vn1 reaches the abut- Figure 2 is a cross section on the line 2-2 of ment formed by the end wall of the slot 12, as 20 Figure 1. shown, this movement of the shaft 11 serving. Figure 3 is a developed view of the abutments to effect the required change in the variable speed shown in Figure 1. gear b in the manner hereinafter described. To In carrying the invention into effect as shown effect another gear change the fluid is released I employ a shaft a for controlling the variableo e Cylinder 0f the acting plunger and 25 speed gear indicatedgenerally by b. The shaft a may be admitted to the cylinder 1' of another is-slidable in bearings c, d, and is connected at one p f, s in the eXamp'le shown, this conend to a plunger 6 carried in a fixed cylinder dition involves a retraction of the shaft a, the to which (when the apparatus is in use) pressure retraction is effected by the pressure of the:con-

fluid is constantly admitted through a pipe 5'. stantly-suppfied fluid on t plunger i 30 In the example shown the shaft a, forms the From the foregoing it will be seen that the sliddriven shaft of the variable-speed gear b, and able shaft (1 is moved in one direction by the the connection between this shaft and the plunger pl ng r 6 d r h pr re f h onstant ye is effected by a hollow cylindrical member g suppli d fluid, a d in t e pp s t di t n by which is slidable in a hollow cylindrical extenany one of the other plungers n O p (1 this 35 sion h of the cylinder f. A key i on the member g latter movement being determined by the correengages a groove 7' in the inner surface of the Sp abutmentextension h and thereby prevents rotation of the n e p e own t e shaft a carries the member g without affecting its sliding movee r W e 02, 1 1 0f the gear and these 40 ment. At one end this member g is screwed onto gear whe ls re p c ively engage r wh l 40 the adjacent and enlarged end of the plunger 6, n 0 11 q splined on the shaft o of the gear and at the other end the said member is formed which receives its motion from a gear wheel in with an inwardly extending annular part adapted engagin n t r s r Wh l 06 a plin d on to bear against the inner end of a thrust bearing the shaft 12*. The shaft 0 also carries spring con- 70 arranged on the adjacent end of the shaft a trolled key pieces y, 2, whereby any one of the 45 between a retaining nut Z and a collar m on the gear wheels e n 0 13 Q2 can be secured to the shaft. The free end of the cylindrical extension shaft or. In the position of the parts as shown the h is provided with four slots (indicated by n, o gear wheel n is secured by the key piece 2 to the p, q, respectively) which are illustrated in a deshaft (1-, the key piece 1/ being out of action. This veloped condition in Figure 3. The end walls of position of the parts is brought about by the ad- 50 these slots form abutments for limiting the outmission of fluid under pressure to the cylinder ward movement of four plungers each preferably containing the plunger 12 and enables the shaft having an eifective area of twice that of plunger 0. to be driven at its highest speed. To enable e (indicated by 11 0 11 q respectively) under the shaft or to be driven at a different speed the the action of pressure fluid admitted tofixed cylfluid is released from the cylinder 7 of the plung- 5 er n and admitted to another of the cylinders r, for example, that containing the plunger 0 This causes the plunger 0 to move into contact with the abutment formed by the end wall of the corresponding slot 0, and the shaft a to be moved in the opposite direction by the plunger e under the pressure of the constantly-supplied fluid until the cylindrical member a abuts against the adjacent end of the plunger 0 In this position of the parts the gear wheel 0 is secured to the shaft a by the key piece 1/, and the key piece 2 is out of action. Further speeds of the shaft 41. may be obtained by releasing the fluid from the cylinder 1 of the plunger 0 and admitting the fluid to either of the other cylinders r. A still further speed may be obtained simply by releasing the fluid from the cylinder 1 of the acting plunger. This enables the shaft a to be moved by the plunger e into a position in which the cylindrical member g abuts against the adjacent side of the block of cylinders T. In this position the gear wheel e is secured to the shaft (1 by the key piece 2 and the shaft is driven at its lowest speed. If it is now required to increase the speed of the shaft (1., pressure fluid is admitted to any one of the cylinders 7 r, and the corresponding plunger is thereby claim as new and desire to secure by Letters Pat-- caused to move the shaft against the action of the plunger e until movement of the operating plunger is arrested by the corresponding abutment.

On the end of the shaft 11 adjacent to the bearing d is keyed a gear wheel 2 which engages another gear wheel 3 for enabling the motion of the shaft to be transmitted to the part to be driven.

By this invention the actuation of a slidable gear controlling member can be effected in a very simple and convenient manner.

The invention is not limited to the examples above described, as subordinate details may be. varied to suit different requirements, but in all cases the movement of the slidable member is effected in one direction by a plunger subjected to constantly-supplied fluid pressure, and in the other direction by additional fluid operated means, the latter movement being limited by suitably arranged abutments.

Having thus described my invention what I ent is:-

1. Means for controlling variable-speed gears,

comprising the combination of a slidable. gear controlling member, a slidable fluid operated member for moving the said gear controlling member in one direction under the action of constantly supplied pressure fluid, a plurality of additional fluid operated members for moving the said gear controlling member in the opposite direction against the action of the first mentioned fluid operated member, and a plurality of abutments for determining the positions to which the said gear controlling member can be moved by the said additional fluid operated plungers.

2. Means for controlling variable-speed gears, comprising the combination of a slidable gear controlling member, a fixed cylinder, 2. plunger slidable in the said cylinder for moving the said gear controlling member in one direction under the action of pressure fluid constantly supplied to the said cylinder, a plurality of additional fluid operated plungers for moving the said gear controlling member in the opposite, direction against the action of the first mentioned plunger, and a hollow member associated with the said cylinder and adapted at one end to provide a plurality of abutments for determining the positions to which the said gear controlling member can be moved by the said additional fluid operated plungers.

3. Means for controlling variable-speed gears, comprising the combination of a slidable and rotatable gear controlling shaft, a fixed cylinder, a non-rotatable plunger slidable in the saidcylinder for sliding the said shaft in one direction under the action of pressure fluid constantly supplied to the said cylinder, a slidable cylindrical member interconnecting the said shaft and plunger, a plurality of additional fixed cylinders, a plurality of additional plungers slidable in the said additional fixed cylinders and adapted to act on the said cylindrical member for sliding the said shaft in the opposite direction against the action of the first mentioned plunger, a fixed hollow cylindrical part associated with one end of the first mentioned fixed cylinder and containing the said cylindrical member, and a plurality of abutments formed by one end of the said hollow cylindrical part for determining by contact with the said additional plungers the positions to which the said shaft can be moved by the said additional plungers.

AXEL CHARLES WICKMAN. 

